/**
 * Design and implement a data structure for Least Recently Used (LRU) cache. It should support 
 * the following operations: get and set.
 * get(key) - Get the value (will always be positive) of the key if the key exists in the cache, otherwise return -1.
 * set(key, value) - Set or insert the value if the key is not already present. When the cache reached its capacity, 
 * it should invalidate the least recently used item before inserting a new item.
 */
/**
 * @author Ivan
 *
 */
package problem146_LRU_Cache;